Universal demarcation point

ABSTRACT

A universal demarcation point for managing the delivery of communications services to a subscriber that provides an interface between a utility distribution network and subscriber owned equipment. The universal demarcation point includes a utility accessible portion and a subscriber accessible portion. The utility accessible portion has an input port, an output port, a plurality of modular connectors, a power supply, and a plurality of service modules. The input port provides access to the universal demarcation point for delivery of communications service from the utility distribution network. The communications services are delivered through a hybrid cable. The hybrid cable has a plurality of fiber optic cables and a plurality of copper cables. The fiber optic cables are capable of transmitting light signals and the copper cables are capable of transmitting electric power. The output port provides access for delivering the communications services from the universal demarcation point into the subscriber&#39;s dwelling. The plurality of connectors are fixedly mounted to the universal demarcation point. The power supply is removably mounted to the universal demarcation point. The power supply converts the electric power into a voltage for powering the operation of the universal demarcation point. The service modules are capable of plugging into the modular connectors and convert the light signals that are transmitted on the fiber optic cables onto cables that are suitable for use in the subscriber&#39;s dwelling. The subscriber accessible portion is adjacent to the utility accessible portion and has ports that enable the subscriber to test the integrity of the communications services delivered from the utility distribution network.

BACKGROUND OF THE INVENTION

The present invention relates to a device that facilitates the deliveryof communications services to subscribers. More particularly, thepresent invention relates to a universal demarcation point that providesan interface between a utility distribution network and subscriber ownedequipment for use with the delivery of communication services tosubscribers via fiber optic and copper cables.

When delivering communications services to subscribers, it is common fora utility to attach a service box to the subscriber's dwelling. Theservice box provides an interface between the utility distributionnetwork and subscriber owned equipment. As used herein, the term“subscriber owned equipment” means equipment that a subscriber attacheseither directly or indirectly to a utility distribution network toreceive or transmit communications services through the utilitydistribution network. Examples of subscriber owned equipment includetelephones, television, and modems.

When the subscriber subscribes to multiple types of communicationsservices, the utility mounts a separate service box to the subscriber'sdwelling for each type of communications service. Each of the separateservice boxes is then connected to the appropriate utility distributionnetwork. For example, the telephone service box is connected to thetelephone distribution network and the cable television service box isconnected to the cable television distribution network.

When the utility provides communications services in rural areas wherethere may be several miles between each subscriber, the utility mustinstall separate copper wires to each service box on each subscriber'sdwelling. In addition, when communications services are transmitted overlong distances using certain types of copper wires, the electricalsignals weaken and become distorted. To overcome these drawbacks, theutility must install amplifiers or repeaters at regular intervals in theutility distribution network so that the utility can provide thesubscriber with a desirable quality of communications services. As aresult of the costs associated with serving subscribers in rural areas,the utilities have been restricted in their ability to providesubscribers with a range of communications services that utilities aretypically able to provide for subscribers in urban areas.

There are various designs for service boxes. One such design isdescribed in Grant, U.S. Pat. No. 4,673,771. The Grant patent disclosesa universal building entrance terminal for telephone service. Theterminal is primarily designed for attachment to commercial buildingswhere it is necessary to gain access to the terminal blocks for adding,deleting or changing subscribers' telephone lines. The terminal has amodular construction that allows components in the terminal to beaccessed and changed.

Several service box designs include the ability to deliver more than onetype of utility service. For example, Nickola, U.S. Pat. No. 3,614,538,discloses a pedestal, which is mounted adjacent to a mobile home, fordelivering electric power, telephone service, and gas service to themobile home. Conventional electric and gas meters, as well as aconventional telephone box, can be mounted to the post so that theutilities can be readily connected and disconnected to the mobile home.

Dively. U.S. Pat. No. 4,785,376, discloses a utility pedestal that isprimarily designed for use in marinas. The pedestal allows for deliveryof electric, telephone, television, and water service to a single point.The pedestal also contains connectors that enable the utility servicesto be conveniently connected and disconnected to a boat or vehicle.

Horn, U.S. Pat No. 5,196,988, and Horn, U.S. Pat. No. 5,184,279,disclose an adapter faceplate for use in a metal power pedestal. Theadapter provides the ability to add telephone and televisioncapabilities to the power pedestal. The adapter isolates the telephoneand television cables from the electrical components in the pedestal.

Frouin, U.S. Pat No. 5,134,541, discloses a distribution system forwater, gas, fuel, electricity, and other fluids. The system is enclosedin a container that resists vandalism and accepts payment fordisbursement of the utility services.

SUMMARY OF THE INVENTION

The present invention includes a universal demarcation point formanaging the delivery of communications services to a subscriber. Theuniversal demarcation point provides an interface between a utilitydistribution network and subscriber owned equipment.

The universal demarcation point includes a utility accessible portionand a subscriber accessible portion. The utility accessible portion hasan input port, an output port, a plurality of modular connectors, apower supply, and a plurality of service modules.

The input port allows a hybrid cable from the utility distributionnetwork to pass into the universal demarcation point. The hybrid cablehas a plurality of fiber optic cables and a plurality of copper cables.The fiber optic cables are capable of transmitting light signals and thecopper cables are capable of transmitting electric power. The outputport delivers the communications services from the universal demarcationpoint into the subscriber's dwelling.

The plurality of modular connectors are fixedly mounted to the universaldemarcation point. The power supply, which is removably mounted to theuniversal demarcation point, converts the electric power into a voltagefor powering the operation of the universal demarcation point. Theplurality of service modules plug into the modular connectors andconverts light signals that are transmitted on the fiber optic cablesonto cables that are suitable for use in the subscriber's dwelling.

The subscriber accessible portion is adjacent to the utility accessibleportion and has ports that enable the subscriber to test the integrityof the communications services delivered from the utility distributionnetwork.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of the universal demarcation point of the presentinvention.

FIG. 2 is a flow diagram illustrating a pathway for communicationssignals through the universal demarcation point.

FIG. 3 is a flow diagram illustrating another pathway for communicationssignals through the universal demarcation point.

FIG. 4 is a flow diagram illustrating yet another pathway forcommunications signals through the universal demarcation point.

FIG. 5 is a flow diagram illustrating still another pathway forcommunications signals through the universal demarcation point.

FIG. 6 is a logic flow diagram for a control service module.

FIG. 7 is a flow diagram illustrating a pathway for video signalsthrough a filter module.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention includes a universal demarcation point, which isillustrated at 10 in FIG. 1. The universal demarcation point 10 providesan interface between a utility distribution network and subscriber ownedequipment for managing the delivery of communications services tosubscribers.

The universal demarcation point 10 is particularly suited for managingthe delivery of audio, video, and computer data services over fiberoptic cables and copper cables to subscribers in rural areas. Theuniversal demarcation point 10 provides a single interface fordelivering the audio, video, and computer data services to subscribers.As a result, the utility only needs to install one hybrid cable toconnect each subscriber to the utility distribution network. Installingonly a single hybrid cable to each subscriber in rural areas also allowsthe utility to reduce the costs that are associated with maintainingseveral separately installed cables that run to each subscriber.

Because of the cost associated with transmitting electrical signals overlong distances to sparsely populated areas, utilities servingsubscribers in rural settings are limited in their ability to deliver avariety of communications services to its subscribers. However, bydelivering various communications services to subscribers through asingle interface, the universal demarcation point 10 allows audio,video, and computer data services to be transmitted on a single fiberoptic cable or in a single bundle of fiber optic cables.

The fiber optic cables have a greater bandwidth than conventionaltwisted pair cables. As a result, the fiber optic cables are capable ofhandling more information than twisted pair copper cables or coaxialcables. Because the fiber optic cables are capable of handling a greaterthroughput of information, it is possible to simultaneously transmitmore than one type of signal, such as audio and video signals, on asingle fiber optic cable.

Fiber optic cables also do not require the frequent use of amplifiers orrepeaters that are required when communications services are transmittedover twisted pair copper cables or coaxial cables. As a result,transmission of the audio, video, and computer data services over thefiber optic cables allows the quality of the communications services tobe improved while lowering the cost of transmitting the communicationsservices.

Utilities that serve urban areas where there are greater densities ofsubscribers have found that they can reap the benefits of transmittingcommunications services with fiber optic cables in a cost effectivemanner by installing fiber optic cables to a central neighborhoodlocation. From this point, the communications services are delivered tosubscribers with twisted pair copper cables or coaxial cables.

However, the sparsely populated nature of rural areas makes itimpractical to install fiber optic cables to either subscribers'dwellings or central neighborhood locations. The universal demarcationpoint, however, now provides a cost effective mechanism for deliveringcommunications services to rural area subscribers with fiber opticcables.

The universal demarcation point 10 has a modular configuration thatallows the universal demarcation point 10 to be modified to manage thedelivery of any type of communication service that is provided by autility. The modular configuration of the universal demarcation point 10allows the universal demarcation point 10 to be installed with a limitednumber of components. When the subscriber requests additional servicesor the utility raises the capital to install the ability to provideadditional services, the utility can readily modify the configuration ofthe universal demarcation point 10 by adding or changing components.

The universal demarcation point is generally divided into a utilityaccessible portion 12 and a subscriber accessible portion 14. Theutility accessible portion 12 includes a motherboard 16. The motherboard16 has a plurality of connectors 20 for attaching components to theuniversal demarcation point 10.

The connectors 20 are preferably a plurality of modular edgeboardconnectors 20. Each of the modular edgeboard connectors 20 is adapted toreceive a complementarily shaped end portion of a service module 22. Themodular edgeboard connectors 20 retain the service modules 22 in adesired position in the universal demarcation point 10 while allowingthe service modules 22 to be readily removed from the universaldemarcation point 10. Modular edgeboard connectors 20 possessing theabove characteristics can be obtained from EDAC Systems Inc. (Colmar,Pa.), Texas Instruments, Inc. (Houston, Tex.) and Sullins ElectronicsCorporation (San Marcos, Calif.).

The end portion of the service module that is shaped complementary tothe modular edgeboard connectors 20 preferably includes conductivetraces. The motherboard 16 preferably also includes conductive traces orwires (not shown) for delivering electrical power from a power supply 24to the modular edgeboard connectors 20 so that the modular edgeboardconnectors 20 can transmit the electrical power to the service modules22 that are plugged into the modular edgeboard connectors 20.

The operation of the universal demarcation point 10 is entirely poweredby electric power from the utility distribution network. Local powerfrom the subscriber is not required to operate any of the components inthe universal demarcation point 10. The ability of the utility toprovide telephone service without the use of local power is one of thedesign requirements for rural utilities to obtain loans from the RuralElectrification Administration under the State TelecommunicationsModernization Plan. 58 Fed. Reg. 66,259 (1993).

The universal demarcation point 10 includes a power supply 24 that isremovably mounted in the utility accessible portion 12. The power supply24 converts the electric power from a transmission voltage that istransmitted through the utility distribution network to a usage voltagethat is required to power the operation of the universal demarcationpoint 10. Power supplies that convert electric power at one voltage toelectric power at a different voltage are known.

In one preferred embodiment, the power supply 24 converts the electricpower from a transmission voltage of approximately −48 volts DC to ausage voltage of ±12 volts DC. The power supply 24 is preferablyselected to exhibit a 10 second peak to peak surge rating at an RF(radio frequency) output of 400 volts. The power rating or capacity ofthe power supply 24 is selected based upon the number of service modules22 that are used in the universal demarcation point 10. When fourservice modules 22 are used in the universal demarcation point 10, thepower supply 24 is preferably selected with a 250 watt power rating.

The power supply 24 preferably plugs into the modular edgeboardconnector 20 on the motherboard 16. The modular edgeboard connector 26connects the power supply 24 to the conductive traces or wires (notshown) on the motherboard 16 while allowing the power supply 24 to beremoved from the motherboard 16.

The utility accessible portion 12 has a fixedly mounted power terminalstrip 28. The power terminal strip 28 provides connections for thecopper cables that power the operation of the universal demarcationpoint 10. The power terminal strip 28 also provides connections for thetwisted pair copper cables when the twisted pair copper cables are usedto provide telephone service to the subscriber. For example, the utilitymay transmit the telephone service over twisted pair copper rather thanfiber optic cables to reduce the initial cost of installing theuniversal demarcation point 10.

The utility accessible portion 12 includes an output port 30 and aninput port 32. The output port 30 allows cables carrying thecommunications services to pass from the universal demarcation point 10to the subscriber's dwelling. The input port 32 allows cables carryingthe communications services from the utility distribution network topass into the universal demarcation point 10. The output port 30 and theinput port 32 are preferably positioned on a lower surface 34 or a backsurface 36 of the universal demarcation point 10 to minimize problemsassociated with substances leaking into the universal demarcation point10.

The utility accessible portion 12 preferably also includes a fiber opticcable management area 40 that is located adjacent to the service modules22. The fiber optic cable management area 40 preferably has a tray 42that is suitable for holding excess or unused portions of the fiberoptic cables. The fiber optic cable management area 40 thereby helps toprotect the fiber optic cables from damage.

The universal demarcation point 10 includes a cover (not shown) for theutility accessible portion 12. The cover protects the components insidethe utility accessible portion 12 from damage that may arise from avariety of sources, such as vandalism or the environment. When the coveris in a closed position, the cover preferably creates a water-tight sealwith the utility accessible portion 12. The cover preferably includes alocking mechanism (not shown) to prevent unauthorized access to thecomponents inside the utility accessible portion 12.

The subscriber accessible portion 14 enables the subscriber to ascertainwhether a problem with communications services is caused by a problem inthe utility distribution network or the subscriber owned equipment. Sucha device is commonly known as a network interface device. Preferably,the network interface device includes a test port for each of thecommunications lines that enter the subscriber's dwelling. For example,an RJ-11 plug and socket 44 are preferably provided for each telephoneline and a coaxial plug and socket 46 are preferably provided for eachvideo line.

Other types of devices can be used in the subscriber accessible portion14 to ascertain whether there is a problem with the utility distributionnetwork or the subscriber owned equipment. For example, the subscriberaccessible portion 14 may include a sensor and an LED (light emittingdiode) 48 to indicate if the communications signal drops below athreshold level.

Similar to the utility accessible portion 12, the subscriber accessibleportion 14 includes a cover (not shown) that protects the test portsfrom damage that may result from a variety of sources, such as vandalismor the environment. When the cover is in a closed position, thesubscriber portion cover preferably creates a water-tight seal with thesubscriber accessible portion 14. The subscriber portion cover may alsoinclude a locking mechanism (not shown) to prevent unauthorized accessto the components inside the subscriber accessible portion 14.

The service modules 22 are selected based upon the desiredcommunications services that the utility is providing to the subscriber.The modular configuration of the universal demarcation point 10 allowsthe universal demarcation point 10 to receive either analog or digitalsignals from the utility distribution network and to transmit eitheranalog or digital signals to the subscriber's dwelling for use on thesubscriber owned equipment.

The modular configuration of the universal demarcation point 10 alsoallows the utility to modify the universal demarcation point 10 todeliver the communications services over different types of cables. Forexample, the video signal can be transmitted from the universaldemarcation point 10 to the subscriber owned equipment using coaxialcable or fiber optic cable.

Preferably, the service modules 22 include an optical receiver servicemodule 22a. The optical receiver service module 22a converts informationtransmitted as a light signal on the fiber optic cable into anelectrical signal that is transmitted on a copper cable.

To convert the light signal into the electrical signal, the opticalreceiver service module 22a preferably includes a conventional PIN-FET(positive intrinsic negative-field effect transistor) photodetector (notshown). The PIN-FET photodetector produces an electrical signal thatvaries based upon the intensity and wavelength of light that strikes thephotodetector. The PIN-FET photodetector preferably possesses thecharacteristics set forth in Table 1. A preferred PIN-FET photodetectorcan be obtained from Epitaxx Inc. (Trenton, N.J.) under the designationETX700.

TABLE 1 Optical Input Range −10 to −1 dBm Optical Wavelength 1300 to1550 nm ± 20 nm Optical Return Loss 40 dB Impedance 75 Ohms Return Loss−15 dB Bandwidth 50 to 550 Mhz (min) Frequency Response ±1 dB InputVoltage 12 Volts DC Current 100 Milliamps Operating Temperatures −40 to+80° C.

The optical receiver service module 22a also includes a monolithicmicrowave integrated circuit (MMIC) amplifier (not shown) that amplifiesthe electrical signal to a radio frequency output of approximately +6dBmV. A preferred MMIC amplifier can be obtained from Hewlett PackardCompany of (San Jose. Calif.) under the designation MAV-11. As one ofordinary skill in the art will appreciate, the optical receiver servicemodule 22a may also use a conventional amplifier to amplify theelectrical signal.

The optical receiver service module 22a preferably includes a removablephysical contact optical connector 72 to connect the PIN-FETphotodetector to the fiber optic cable. The physical contact opticalconnector 72 is preferable because it provides a low return loss whileallowing the optical receiver service module 22a to be quicklydisconnected from the fiber optic cable. A preferable physical contactoptical connector 72 can be obtained from Siecor Corporation (Orlando,Fla.) under the designation FC-PC.

Once the optical receiver service module 22a converts the communicationsservices into the electrical signal, the electrical signal is separatedinto the individual communications services. Preferably, thecommunications services are transmitted in discrete wavelength regionsso that the individual communications services can be separated byfiltering based upon wavelength. Other conventionally known techniquescan be used when the communications services are transmitted in adigital format.

The optical receiver service module 22a also includes separate modularconnectors 64 that provide a connection for cables that carry theindividual communications services from the utility accessible portion12 to the test ports 44, 46 in the subscriber accessible portion 14. Forexample, when the optical receiver service module 22a delivers videosignals, the optical receiver service module 22c preferably includes anSMB connector that provides a connection to a coaxial cable.

To assist in monitoring the status of the incoming light signal on thefiber optic cable, the optical receiver service module 22a includes aninput signal LED 66 that illuminates to indicate when the light signaldrops below a threshold value. Preferably, the input signal LED 66illuminates when the light signal drops below −10 dBm.

The optical receiver service module 22a also includes a receiver powerLED 68 that indicates the power supply is providing electric powerwithin a desired range to power the operation of the PIN-FETphotodetector and the MMIC amplifier. Preferably, the receiver power LEDilluminates when the electric power is approximately −12 volts.

The optical receiver service module 22a is preferably encased in anouter layer of sheet metal 70. The sheet metal layer 70 protects thecomponents in the optical receiver service module 22a from damage andshields the other components in the universal demarcation point 10 frominterference by radio frequency radiation emissions.

The service modules 22 also preferably include an optical transmitter22b for converting electrical signals into light signals that aretransmitted from the universal demarcation point 10 to the utility overfiber optic cables. The electrical signals are preferably converted intolight signals using a Fabry-Perot laser (not shown). Variations in theelectrical signals cause the laser to vary the current through a lightsource. The laser is preferably a Fujitsu Lightwave semiconductor, whichcan be obtained from Fujitsu America, Inc. (Lake Bluff, Ill.) under thedesignation FLD130C2PL.

The optical transmitter service module 22b has modular connectors 78that provide a connection to the cables that transmit the communicationsservices from the subscriber. For example, when the optical transmitterservice module 22b delivers video signals, the optical transmitterservice module 22b preferably includes an SMB connector that provides aconnection to a coaxial cable.

The optical transmitter service module 22b preferably includes thecapability to transmit several communications services from thesubscriber to the utility distribution network over a single fiber opticcable. To facilitate transmitting more than one communications serviceon the fiber optic cable, the communications services are preferablytransmitted at different wavelengths.

Similar to the optical receiver service module 22a, the opticaltransmitter service module 22b preferably includes a transmitter powerLED 74 that indicates the power supply is providing electric powerwithin a desired range to power the operation of the components in theoptical transmitter service module 22b. Preferably, the transmitterpower LED 74 illuminates when the electric power is approximately −12volts.

The laser is preferably connected to the fiber optic cable with aremovable physical contact optical connector 76. The physical contactoptical connector 76 is preferable because it provides a low return losswhile allowing the optical transmitter service module 22b to be quicklydisconnected from the fiber optic cable. A preferable physical contactoptical connector 76 can be obtained from Siecor Corporation (Orlando,Fla.) under the designation FC-PC.

The utility preferably connects the utility distribution network to theuniversal demarcation point 10 with a hybrid cable 60. The hybrid cable60 contains a plurality of fiber optic cables and a plurality of coppercables. The number of fiber optic and copper cables is selected basedupon the type of communications services that the utility is providingto the subscriber and the number and type of service modules 22 in theuniversal demarcation point 10. When the universal demarcation point 10is being used with a residential dwelling, the hybrid cable 60preferably includes four single-mode fiber optic cables and four 16gauge braided copper cables.

The hybrid cable 60 has a protective coating 86 to protect fiber opticand copper cables from damage. The protective coating 86 is selectedbased upon where the hybrid cable 60 is installed. For example, a doublelayer polyethylene jacket with a single armor layer is suitable forprotecting the fiber optic and copper cables when the hybrid cable 60 isinstalled underground. A hybrid cable 60 having the abovecharacteristics can be obtained from AT&T Fitel (Carrollton, Ga.).

When the hybrid cable 60 contains four fiber optic cables, a first fiberoptic cable is preferably used to transmit the audio, video, andcomputer data signals to the subscriber and a second fiber optic cableis preferably used to transmit the audio, video, and computer datasignals from the subscriber. A third fiber optic cable and a fourthfiber optic cable are spares that can be used to replace a defectivefiber optic cable. In the alternative, the third fiber optic cable canbe used to provide a high speed computer data link (greater than 1.5Mbps) between the subscriber and the utility.

When the hybrid cable 60 contains four 16 gauge braided copper cables,two of the braided copper cables provide electric power for theoperation of the components in the universal demarcation point 10. Theother two the braided copper cables are preferably used to provideconventional telephone service to the subscriber.

The service modules 22 may also include a control service module 22c.The control service module can be programmed using conventionaltechniques to perform a variety of tasks in the universal demarcationpoint 10. For example, the control service module 22c can monitor theoperational status of the other service modules 22 and notify theutility if a problem arises. When the control service module 22c is usedto modify the other service modules 22, a data path 80 is providedbetween the service modules.

The control service module 22c can also be programmed to activelycontrol the operation of the other service modules or other utilitymeters. For example, the control service module 22c can be assigned anidentification number, similar to “caller id”, that is unique to eachsubscriber. The identification number allows the utility to remotelymonitor each subscriber's usage of utility services, such as naturalgas, water, and electricity and then transmit the readings to theutility. By remotely monitoring each subscriber's use of utilityservices, the utility reduces the costs associated with manually readingthe utility meters at the subscriber's dwelling. Remote monitoringsystems having the above characteristics are described in Brennan. Jr.et al., U.S. Pat. No. 5,243,338, and Venkataraman et al., U.S. Pat. No.4,862,493. The identification number also enables the utility to shutoff power to the building in the event of a fire or if the subscriber isdelinquent in paying for the communications services.

The control service module 22c also preferably includes the ability tomonitor when there is unauthorized access to the utility accessibleportion 12. The control service module 22c not only notifies the utilitythat there has been unauthorized access to the utility accessibleportion 12 but also preferably stops all transmission of communicationsservices to and from the subscriber until the utility resets theuniversal demarcation point 10. By stopping all transmission ofcommunications services, the control service module 22c deterssubscribers from tampering with the components inside the utilityaccessible portion 12.

Because the universal demarcation point 10 provides a source for theentry of all or substantially all of the utilities to the building, itprovides a central bonding location from which all of the utilities canbe grounded. Thus, the possibility of electrical problems resulting froman improper ground are minimized.

The modular construction of the universal demarcation point 10 allowsthe universal demarcation point 10 to operate in a variety ofconfigurations. Once the universal demarcation point 10 is mounted tothe subscriber's dwelling, the universal demarcation point 10 allows theutility to later offer the subscriber additional communications servicesthat would not be feasible without already having access to thesubscriber's dwelling.

In the following flow diagrams, each of the components is generallyidentified as being within the boundaries of the universal demarcationpoint 10. One of ordinary skill in the art would appreciate that theplacement of the components in particular service modules 22 is a designchoice based upon the size of the service modules 22 and the desiredfeatures of the service modules 22.

The universal demarcation point 10 allows the audio, video, and datasignals to be transmitted from the utility distribution network on afiber optic cable and to the utility distribution network on anothersingle fiber optic cable, as illustrated in FIG. 2.

The incoming light signal is transformed into an electrical signal withan optical receiver. After being converted into an electrical signal,the electrical signal is separated audio, video, and computer datasignals based upon differences in the wavelengths that the signals aretransmitted at. The separate audio, video, and computer data signals arethen transmitted to an audio, video, or computer data output processor,respectively. The audio, video, and computer data output processorsconvert the signals into a form that can be utilized by the subscriber.For example, the audio signal is preferably transmitted into thesubscriber's dwelling using a twisted pair copper cable having RJ-11connectors and the computer data signal is preferably transmitted intothe subscriber's dwelling using either the RS 232 or RS 485 protocols.

This preferred embodiment of the universal demarcation point alsoincludes the capability for transmitting audio, video, and computer datasignals from the subscriber. The separate incoming audio, video, andcomputer data electrical signals are first multiplexed onto a singlecopper cable based upon the different wavelengths that the signals aretransmitted at. The electrical signals are then transmitted using coppercable to an optical transmitter where the electrical signals areconverted into light signals that are transmitted through the utilitydistribution network on a fiber optic cable.

With this preferred embodiment, the operation of each of the componentsis preferably monitored by a control service module. When the controlservice module senses that there is an error with one of the components,the control transmits an error message to the utility. The error messageis multiplexed with the audio, video, and computer data signals fortransmission through the utility distribution network on a fiber opticcable.

The universal demarcation point of the present invention also enablesthe incoming and outgoing audio, video, and computer data signals to betransmitted on a single fiber optic cable as illustrated in FIG. 3. Withthis embodiment, the light signal from the utility distribution networkis preferably separated from the light signal being transmitted to theutility distribution network using a conventional multiplexer. Theconventional multiplexer is preferably obtained from JDS Fitel (Ottawa,Ontario, Canada) under the designation WD-1315X. Then, the incominglight signal is processed similar to the procedure described withreference to the embodiment illustrated in FIG. 2.

After the outgoing audio, video, and computer data signals are convertedinto light signals as described above with reference to the embodimentillustrated in FIG. 2, the light signals are then transmitted to theutility distribution network by combining the outgoing light signalswith the incoming light signals using a conventional multiplexer. Alsosimilar to the embodiment illustrated in FIG. 2, the operation of eachof the components in this embodiment is monitored by a control servicemodule.

In yet another embodiment of the universal demarcation point of thepresent invention illustrated in FIG. 4, incoming audio and videosignals are transmitted from the utility distribution network on a firstfiber optic cable. This embodiment includes a decoder to decode thecommunications services from a digital signal. Outgoing audio and videosignals are transmitted from the subscriber on a second fiber opticcable. This embodiment also includes an encoder to encode thecommunications services into a digital signal.

This embodiment also illustrates that both the outgoing and incomingcomputer data signals are transmitted and received on a third fiberoptic cable. By using a separate fiber optic cable to transmit andreceive only computer data signals, this embodiment enables the computerdata transfer to occur at greater rates than when the computer datasignals are combined on a single fiber optic cable with audio or videosignals.

Still another embodiment of the universal demarcation point of thepresent invention is illustrated in FIG. 5. This embodiment illustratesthe universal demarcation point as receiving video and data signals on afiber optic cable. The optical receiver converts the light signals intoan electrical signal. The electrical signal is then separated intoindividual video and data signals that can be transmitted into thesubscriber's dwelling using conventional cables such as twisted paircopper conductors or coaxial cable.

To reduce the cost of manufacturing the universal demarcation point withan optical transmitter as well as an optical receiver, the universaldemarcation point accepts audio signals on a twisted pair copper cable.However, it is noted that the modular construction of the universaldemarcation point allows the utility to later upgrade the universaldemarcation point to include the incoming and outgoing audio signals onthe fiber optic cables.

The operational status of the components in the universal demarcationpoint are monitored with the control service module, illustrated at 22cin FIG. 1. The logic followed in one embodiment of the control servicemodule is set forth in FIG. 6. The control service module begins eachcycle by sensing whether the power supply is providing electric powerwithin a specified operating range. If the electric power is not withinthe operating range, the control service module sends an error messageto the utility indicating the error. The control service module thenmonitors the operation of the optical receiver, the decoder, the videooutput unit, the data output unit, and the audio transmission level. Ifany of these values are not satisfactory, the control service moduletransmits a corresponding error message to the utility. The monitoringprocess is continually repeated while the universal demarcation pointremains connected to the utility distribution network.

The universal demarcation point may also include a filter module, suchas is illustrated in FIG. 7. The filter module enables the utility tocontrol the channels that the subscriber is able to view. The filtermodule enables the utility to transmit unscrambled video signals throughthe utility distribution network. By transmitting unscrambled videosignals through the utility distribution network, the utility is able toprovide higher quality video signals to the subscribers. Because thevideo signals are transmitted from the utility distribution network onfiber optic cable, which is difficult for unauthorized users to tapinto, it is not necessary for the utility to transmit scrambled videosignals.

Prior to entering the filter module, the video signal is preferablysplit into two lines (lines 1, 2). Line 1 is directed through filter 1where the video signal is filtered so that only the off-air videosignals remain on line 1. Alternatively, the off-air video signals canbe obtained from a separate source such as an antenna or a satellitedish.

Line 2 is directed into the filter module where the video signal isfiltered to produce video signals that the utility restricts access tobased upon the services that the subscriber pays for. By restrictingaccess to certain services, the utility is able to charge the subscriberadditional fees to receive the services.

Line 2 is preferably split into a plurality of lines. Each of the linesis filtered so that only a desired portion of the video signal remainson the lines. After each video signal is filtered, each video signalpasses through a controller. The controller either allows the videosignal to pass through or blocks the video signal based upon whether thesubscriber has paid for the desired channel. For example, the videosignals can be divided into basic cable television services, premiumchannels, and pay per view channels.

The operation of each of the controllers is controlled by a controlsignal (line 4) from the control service module. The control signalpasses through the master controller where the control signal isdirected to the appropriate controller.

The master controller may also transmit a signal to a controller in theoff-air video signals lines (not shown) so that a portion of the off-airvideo signals are blocked when the subscriber is receiving a premiumchannel or a pay per view channel. By transmitting more than one videosignal on each channel the utility is able to increase its ability tooffer subscribers a greater variety of programming within a givenbandwidth.

The filter module also preferably include system services video andaudio signals (line 6). While line 6 indicates that the system servicesare brought in on a single cable, one of skill in the art willappreciate that separate cables can be used to transmit audio and videosignals. When the audio and video signals are transmitted on separatecables, a conventional multiplexer is preferably included in the cableto enable each of the signals to be transmitted to the RF modulator. Asindicated in FIG. 7, the RF modulator preferably produces a signal thatcan be viewed by the subscriber on channel 3.

After the system services signal passes through the RF modulator, thesystem services signal passes through a controller. Similar to the othercontrollers, the controller is controlled by a signal from the controlservice module that is transmitted to the controller through the mastercontroller.

Prior to being transmitted out of the filter module, each of the videosignals are preferably joined onto a single cable. After being joinedonto the single cable, the video signals are preferably amplified usinga conventional amplifier. The conventional amplifier returns the videosignals to a level that is needed for use by the subscriber.

After the video signals exit the filter module, the video signals arejoined with the off-air video signals onto a single cable (line 8).Placing all of the video signals on the single cable allows thesubscriber to plug the single cable into the subscriber owned equipmentand obtain all of the video services.

Although the present invention has been described with reference topreferred embodiments, workers skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the invention.

What is claimed is:
 1. A universal demarcation point for managing thedelivery of communications services to a subscriber by providing aninterface between a utility distribution network and subscriber ownedequipment, the universal demarcation point comprising: a utilityaccessible portion comprising: an input port in the universaldemarcation point for delivering the communications services from theutility distribution network, the communications services beingdelivered through a hybrid cable having a plurality of fiber opticcables and a plurality of copper cables, the fiber optic cables arecapable of transmitting light signals, the copper cables are capable oftransmitting electric power; an output port in the universal demarcationpoint for delivering the communications services into the subscriber'sdwelling; a plurality of modular connectors fixedly mounted to theuniversal demarcation point; a power supply removably mounted to theuniversal demarcation point, the power supply converting the electricpower into a voltage for powering the operation of the universaldemarcation point; and a plurality of service modules that are capableof being plugged into the modular connectors, the service modulesconverting light signals that are transmitted on the fiber optic cablesonto cables that are suitable for use in the subscriber's dwelling; anda subscriber accessible portion being adjacent to the utility accessibleportion and having ports that enable the subscriber to test theintegrity of the communications services delivered from the utilitydistribution network.
 2. The universal demarcation point of claim 1 andfurther comprising a motherboard that is removably mounted to theuniversal demarcation point in the utility accessible portion, whereinthe plurality of modular connectors are mounted to the motherboard, themotherboard comprising a plurality of conductive traces formed on themotherboard, the conductive traces are capable of transmitting theelectric power from the power supply to the service modules.
 3. Theuniversal demarcation point of claim 1 wherein the plurality of servicemodules includes a video service module.
 4. The universal demarcationpoint of claim 3 wherein the video service module includes a receiverfor converting light signals into electrical signals and transmittingthe electrical signals on a coaxial cable.
 5. The universal demarcationpoint of claim 4 wherein the video service module includes a transmitterfor converting electrical signals into light signals and transmittingthe light signals on a fiber optic cable.
 6. The universal demarcationpoint of claim 5 wherein the video service module further includes amultiplexer, the multiplexer enabling the light signals that aretransmitted by the transmitter and received by the receiver to becarried on a single fiber optic cable.
 7. The universal demarcationpoint of claim 1 wherein the plurality of service modules includes anaudio service module.
 8. The universal demarcation point of claim 7wherein the audio service module includes a receiver for converting thelight signals into electrical signals and transmitting the electricalsignals on twisted pair copper cables.
 9. The universal demarcationpoint of claim 8 wherein the audio service module includes a transmitterfor converting electrical signals into light signals and transmittingthe light signals on a fiber optic cable.
 10. The universal demarcationpoint of claim 9 wherein the audio service module further includes amultiplexer, the multiplexer enabling the light signals that aretransmitted by the transmitter and received by the receiver to becarried on a single fiber optic cable.
 11. The universal demarcationpoint of claim 1 wherein the plurality of service modules includes acomputer data service module.
 12. The universal demarcation point ofclaim 11 wherein the computer data service module includes a receiverfor converting the light signals into electrical signals andtransmitting the electrical signals on computer cable.
 13. The universaldemarcation point of claim 12 wherein the computer data service moduleincludes a transmitter for converting the electrical signals into lightsignals and transmitting the light signals on a fiber optic cable. 14.The universal demarcation point of claim 13 wherein the computer dataservice module further includes a multiplexer, the multiplexer enablingthe light signals that are transmitted by the transmitter and receivedby the receiver to be carried on a single fiber optic cable.
 15. Theuniversal demarcation point of claim 1 wherein the plurality of servicemodules includes a control service module.
 16. The universal demarcationpoint of claim 15 wherein the control service module includes a receiverfor receiving signals from a utility meter to monitor the usage ofutility services flowing through the utility meter.
 17. The universaldemarcation point of claim 16 wherein the control service module furtherincludes a transmitter for transmitting signals to the utility meter tocontrol the flow of utility services through the utility meter.
 18. Theuniversal demarcation point of claim 15 wherein each of the servicemodules contains a monitoring port, each of the monitoring portstransmitting signals to the control service module.
 19. The universaldemarcation point of claim 18 wherein the control service modulecontains a receiver for receiving the signals from the monitoring portsand a transmitter to transmit the signals over the fiber optic cables.20. The universal demarcation point of claim 15 and further comprising agrounding terminal that provides a central ground for all utilityservices delivered through the universal demarcation point.
 21. Theuniversal demarcation point of claim 18 wherein the plurality of servicemodules includes a filter module, the filter module comprising: aplurality of filters to separate portions of the electrical signals fromthe video service module; and a plurality of controllers associated witheach filter, the controllers being in communication with the controlservice module to block portions of the electrical signals fromtransmission to the subscriber owned equipment.
 22. A universaldemarcation point for managing the delivery of communications servicesproviding an interface between a utility distribution network and asubscriber's equipment, the universal demarcation point comprising: autility accessible portion having the following components: an inputport for receiving an input cable carrying the communication servicesfrom the utility distribution network, said input cable comprising atleast one fiber optic cable; an output port for delivering at least oneof the communications service to the subscriber's equipment through atleast one output cable; means for powering said universal demarcationpoint; at least one connector mounted within said utility accessibleportion; at least one service module that is capable of being connectedto at least one of said at least one connector, said at least oneservice module being capable of converting light signals that aretransmitted on said input cable onto one of said at least one outputcable such that the at least one communication service is suitablytransmitted to the subscriber's equipment; and a subscriber accessibleportion positioned adjacent to said utility accessible portion, saidsubscriber accessible portion having ports that enable the subscriber totest the integrity of the communications services delivered from theutility distribution network.
 23. A universal demarcation point asrecited in claim 22, said powering means receiving power from theutility distribution network through said input cable.
 24. A universaldemarcation point as recited in claim 23, said input cable furthercomprising at least one copper cable for providing power to saidpowering means.
 25. A universal demarcation point as recited in claim22, said output cable is selected from the group consisting of twistedpair, coaxial cable, hybrid cable and fiber optic cable.
 26. A universaldemarcation point as recited in claim 22, said at least one servicemodule selected from the group consisting of a video service module,audio service module, and computer data service module.
 27. A universaldemarcation point for managing the delivery of communications servicesproviding an interface between a utility distribution network and asubscriber's equipment, the universal demarcation point comprising: autility accessible portion having the following components: an inputport for receiving an input cable carrying the communication servicesfrom the utility distribution network, said input cable comprising atleast one fiber optic cable; an output port for delivering at least oneof the communications services to the subscriber's equipment through atleast one output cable; a power supply which converts electric powertransmitted through said input cable to a usage power required to powerthe universal demarcation point; at least one connector mounted withinsaid utility accessible portion; at least one service module that iscapable of being connected to at least one of said at least oneconnector, said at least one service module being capable of convertinglight signals that are transmitted on said input cable onto said atleast one output cable such that the at least one of the communicationservices to the subscriber's equipment; and a subscriber accessibleportion positioned adjacent to said utility accessible portion, saidsubscriber accessible portion having ports that enable the subscriber totest the integrity of the communications services delivered from theutility distribution network.
 28. A universal demarcation point asrecited in claim 26, said at least one service module selected from thegroup consisting of a video service module, audio service module, andcomputer data service module.